Yes, probably in some cases.

If there are security cameras and if their presence is advertised, then that probably would be a deterrent to some although not for suicide bombers. However, cameras helped catch the Boston Marathon bombers and so security cameras can be very helpful in catching, if not preventing, many different kinds of crimes.

I think that they don't. NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NNNNNNNNNNNNNNOOOOOOOOOOOOOOOOOOOOOOOOOOOO NNNNNNNNNNNNNNNNNNNNNNNNNNNNNOOOOOOOOOOOOOOOOOOOOOOOOOO NNNNNNNNNNNNNNNNNNNNOOOOOOOOOOOO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO

But they solve them.

No, security cameras do not help prevent terrorist attacks in crowded areas, because most people who commit terror do not care whether they are caught. Cameras did not protect against the Boston Bombings. But it was good to help catch the perpetrators after the fact. Someone bent on terror does not care about being identified.

They may encourage terrorism

So long as a terrorist is able to set up their apparatus of destruction in private, and move it around with little suspicion they should be able to execute a plan regardless of cameras. Therefore it is a question of deterrence, and if anything terrrorists prefer exposure and getting on camera because it helps spread the message and incite fear.

They want to be noticed

Camera would not help prevent an attack. The whole point of a terrorist attack is the fact that they want to cause fear and they want you to know who it is. The camera would actually help their cause and most people that commit a terrorist attack do not survive the attack. These security cameras are mainly there to prevent other crime as well as to keep the general peace.

Security cameras are post-hoc measures.

A security camera will allow law enforcement to find people of interest with greater ease and do their jobs more effectively, but terrorism is a public event and the presence of cameras will not deter the events.The only effective prevention tactics will be making infiltration of terrorist cells and organizations easier.